Method of charging coke ovens



Novg, 1932- R, M. FoLsoM 1,886,948

METHOD OF CHARGING COKE OVENS Filed May 4. 1927 5 vSheets-Sheet l Nov. 8,1932.

R. M. FOLSQM METHOD OF CHARGING COKE OVENS Filed. May 4, 1927 5 SheeiS-She/t 5 Patented Nov. 8, 1932 tasten narran STATES rasant etnica Y ROBERT IVI. FOLSOM, OF READING, MASSACHUSETTS, ASSGNOR '1'0 NEW' ENGLAND FUEL AND TRANSPORTATION 'coMrANn TnusTnns METHOD or GHABGTNG come ovnNs Application filed May 4, 1927.v Serial No. 188,764.

l lliyinvention relates to Amethods of pro@ ducing gas and coke, andV among other things is particularly concerned with an improved wa f ci' charging a retort coke oven.

i The invention will be best understood from the following description when read in the light of the accompanying drawings illustrating an example of apparatus for carrying out the improved method,while the scope 1 of the invention will be `more particularly pointed out in the appended claims.

ln the drawings Fig. l is a longitudinal section of an oven and coal'hopper constructedaccording to the l invention with associatedapparatus shown in elovatiomthisfigureindicating the charge of coal flowing into the oven; Y Y Y F ig. 2 is a section of the oven on the line 242 oFig. l;

F 3 is a plan of theroofof'anoven construc'tedaccording to Figl; y

. Fig. 4e is a plan on an enlarged scale of the rooi' of an oven at the charging hole;

Figs. 5 and 6` respectively Vare sections on 'M2 the lines 5-5 and 6-6 of Fig. 4; Y i

Fig. Y is'an elevation on an enlarged scale of the larry car as viewed from the right in Fig. l:

i Fig. 8 is a section et the chute and valve of i the larry car hopper' on the line 2-2 of Fig.

Fig. 9 1s a schematic diagram of one form of piping for the apparatus; and 'i Fig. lO'is a section on the line lO-lO of ii to this example..

The drawings show a bat-tery of narrow, high-chambered, horizontal coke ovens l seps `ited by combustion chambers 3. Beneath the coke ovens and combustion chambers are parallel crossregenerators 5 of known cens'truction for heating, the air supplied the foinbustion chambers by way of the ducts 7, the fuel for combustion purposes being sup- ,plied by gas nozzlesa). Herein each oven adjacent the center of itsflength is provided with a charging opening 11 having a removable cover 12,7while near opposite ends re; spectively each oven is provid-ed with a gas oll'take 13 in communication with a standpipe 15,1the top bends i6 of various standpipes leading to gas collecting mains 17 at corresponding sides of l the battery. 'As shown each standpipe has a minimally controlled valve 19 for establishing and vinterrupting communication with thelrespective mains. Y

As illustrated the battery at opposite sides respectively is provided with a steamfmain 2l, branch pipes 28 leading from these mains to the upper portions of the adjacent standpipes to Yprovide for projecting steam jets along the top bends 16 of the standpipes for creating in each standpipe an ejector action accelerating flow` of gas from the respective ovens. vEach pipe 23 conveniently may be providedwth a controlling valve 25 for creating the ejector action when desired. I

Herein the mains 17 are connected by a cross over pipe 27, and discharge into a main 29 which leads to gas coolers 31. For drawing the gases from the ovens through the coolers exhausters 33 are provided, the de# sired degree of pressure in thecollecting mains 17 beingmaintained by automatic pressure controllingmechanism 35, the valveof which is indicated at 37.' Y

As illustrated each oven at opposite ends is provided with removable doors 89 which are removed when the oven is pushed. One of the doors 39 is shown as provided with a tracks 47 supporting the wheeled larry cark 49, the hopper of which is indicated at 5l. As illustrated. the hopper hasl the. flared sides 58 which with the vertical baiile 55 cause the coal in the hopper to gravitate through the chuteV 57 uninterruptedly in a continuous stream when'the quick opening valve 59 is moved from its closed dotted line position in Fig. 7 to its open full line position by the Y oven and distributed uniformly and evenly throughout its length without substantial mechanical leveling. Asthe phenomena underlying this action are not exactly known to applicant I will now describe the proportions of one apparatus and the method of operation which exemplify and will secure this result, it being understood however that I am not limited to the proportions anddimensions and particular steps described as wide deviations in these may be made without parting from the spirit of the invention.

VIn this particular example of apparatus referred to the oven chamber is about Ll0 feet long between the inner sides of the doors 39, about 13 feet high, the height being of the order of'one-third of the length, and 17 inches wide at the coke side of the battery, tapering to 15 inches wide at the pusher side of the battery, the coal space of the oven occupying about 620 cubic feet and extending to within about 12 inches of the top of the oven chamber, and the walls of the oven being at about 2800 degrees Fahrenheit during charging. In this oven the charging hole is a rectangle (see Figs. 4, 5 and 6) the dimensions of which are 14 by 20 inches, the narrow side of this rectangle corresponding to the inside width of the oven at its top, while the long side lies in the direction of the length of the oven, it thus being observed that the charging opening is materially elongated in the direction of the length of the oven. The larry'car hasa capacity upward of about 14 gross tons and is provided with a rectangular chute theinside dimensions of which are 17 by 23 inches, being of corresponding geo? metric shape to the cross section of the charging hole. The coal preparatory to charging is pulverized, the degree of lineness being such that about of the coal will pass through a screen having one-eighth inch'square holes.

As an example of the method of operating the above described particular example of apparatus, the pressure controlling valve mechanism conveniently maybe set to maintain a pressure of the order of several millimeters of water above atmospheric in the two gas collecting mains at opposite sides of the battery. When an oven is to be chargechboth valves 19 associated with that oven are opened, and the steam ejectors setin operation by opening the valves 25. rlhe charging hole cover 12 havingbeen removed, the larry containing about 18% gross tons of coal is moved to place the latter over the oven 'with the chute of the' hopper presented to the charging hole. rllhe valve 59 Yis then opened, preferably quickly, .to allow the coal precipitately to enter the charging hole in a continuous stream suflicient to fill the charging hole as the coal gravitates through it. I have found, under these conditions, that with coal of for example about 3 per cent moisture content, the entire charge will flow into the oven andcdist-ribute itself therein evenly, except for occasional small surface irregularities, throughout the length of the oven without mechanical leveling; After the charge of coal has gravitated out ofthe larry, the latter may be moved from over the oven, and the small pile of coal remaining on the oven roof about the charging opening may be swept into said opening as the Coal .gravitates thereinto; and, when the coalhas gravitated to below the top of the charging opening, the cover maybe placed in position and theopening sealed. A single stroke ofA the 'leveling bar to just past the charging hole will then suffice to insure removalof any hump in the coal, caused by sweeping inthe spillage on top of the oven, that may then exist beneath the charging opening, or other small irregularities in the top of the coal .that has been self-distributed as above described. f

Conveniently, under some'conditions of operation, the hopper on the larry car may be charged with an amount of coal greater than that which corresponds to the volumetric capacity of the coal space of the oven, and in charging the oven'. all the Vcoal from the hopper, or sufficient coal, lmay be allowed to flow into the oven to fill the latter to above the upper level of the'coal space, whereupon the leveling bar may be entered into the oven to the full length ofthe latter and withdrawn, which will compact the charge and pull from the oven any excess of coal above that necessary to fill the coal space, such coal pulled from the oven being received in the usual known manner by the spillage receptacle carried by the leveling machine.

My explanation of the above described phenomenajis that' the rapid generation of gas from the pulverized coal flowing into the oven, and possibly someentrapping of air by the rapidly enteringv coal, together with the withdrawal of gas from opposite ends of the oven, destroys that property of the coal which gives it its normal angle of repose, and in effect gives the coal that property of a liquid which causes it -to flow'into a container through an orifice and distribute itself throughout the container by gravity.

I' have found that normally best Vresults will be secured by abruptly` initiating the flow of coal into the oven to the full coal conductingv capacity of the charging opening, and by so proportioning the dimensions of the charging openin g, relative to both the degree of fluidity of the cold coal leaving the larry, and the degree of fluidity of the coal that is distributing itself in. the oven, that the coal is charged at such rate as will pre- Cil vent it froln'becoming unduly stickyv in the oven due to the liberation of tar or otherwise affected to cause its flow to be retarded after it enters the oven.

Ordinarily best results will be obtained With a high chambered oven, such as that described herein, and /When the charging opening is materially elongated in the direc'- tion of the length of the oven. Preferably, for a given oven and coal, the charging opening is designed to handle the coal at about its normal moisture content, it being understood that the uidity of cold coal decreases with an increase in its moisture content. Vhen, under normalconditions, the moisture content of the coal isvery high, and the apparatus vis designed for coal of normal moisture `content,it may be necessary to operate the leveling bar after from about to 7 5% of the charge has entered the oven.

Thebest location of the charging hole Will depend to some extent upon the degree of taper of the oven, it being observed that if the charging hole is at the exact center of the oven, and the latter is tapered, a greater volume of coal must'be charged toward the coke side of the oven than toward the pusher side of the oven, and that at the sameV time the narrowing of the oven from the charging hole toward the pusher side due to its taper acts to retard the fioW of coal in that direction, While the increase in Width of the oven from the charging hole toward the coke side of the oven acts to facilitate flow toward the coke side of the oven. I have found that with an oven proportioned as above described .the retarding effect on the flow of coal of the taper of the oven from the charging hole toard the pusher side of the oven Will be about compensated for by the lesser volume of coal charged into that side, Which results in per'- mitting the-charging hole to be placed at abput the center of the length of the oven.

in practicing 'the above method, preferably gas is Withdrawn-at such rate, during charging, as to prevent a material rise ofY pressure in the oven. To this end the oven chan'iber at its top is preferably maintained at about atmospheric pressure during charging, so as te prevent escape and loss of gas or intake of air through the chuck hole and other oven penings and through the coal'V in the charging opening. This will prevent the emission into the open airof smoke during the charging operation, and save the rich gaseous products then rapidly generated. After charging, the ejectors may be shut oif, Whereupon the pressures in the tops of the ovens Will become and be maintained slightly above atmospheric, which Will maintain the flow of gas into the collecting mains andV also eliminate `any draft effect which might otherwise exist tending to draw air from theregenen ators through the oven floors.

In the appended claims by horizontal retort coke ovennandwords of similar import is meant that type of coke oven With Which the coke is pushed horizontally from oneof the oven ends, the oven chamber. having exteriorly heated side Walls Which are spaced a relatively short distance aparty as compared with the length of the chamber. By elongated coke oven and Words of similar import is meant a coke oven having a coking chamber the length of which is so much greater than its height that coal having anormal angle of repose charged into Vthe chamber through an opening in the oven roof Will not fill said chamber up to the normal charge level if' vas would occur, forexample, With a Vertical type oven orl a horizontal' oven having a chamber With relatively short, horizontal d1- mensions comparedV to its. vertical dimension.

It Will be understood that I am not limited i tothe examples ofapparatusnor to the dimensions or proportions thereof herein de-V scribed, nor to the steps ofthe example of the method herein described, but that Within; the

scope of the invention Wide deviations: may if be made from these Withoutldeparting from the spirit ofthe invention. 'v

I claim:

1.'The method of charging a horizontally elongated retort coke oven ywith coal which comprises delivering pulverized coa-l to the oven at the top thereof through coalconducting means inthe oven roof While the Walls of the oven are hot enough to evolve gas from the coal Wirth such rapidity that substantially "l as it enters they oven the coal vdistributesjby gravity from beneath said coal conducting means toapproximately a uniform height throughout the lengthV of Ithe-oven.

, 2. The method'of charging ahorizontally 'l elongated retort 'coke oven With coal which comprises delivering pulverized coal tothe oven at the topl thereof througha substantialf ly single charging opening in the oven roof While the Walls of the oven are het enough to evolve gas from the coal with such rapidity that substantiallyas it enters theoventhe coal distributesby gravity frombeneath said charging opening to approximately a uni- -formheight throughout the length Aof the oven. v l

3. The method of charging a horizontally elongated retortfcoke oven with coal' which comprises delivering pulverized coal to the oven at the top thereof through coal- Vconductgated, horizontally pushed retort coke oven which comprises ldelivering a charge of pulverized bituminous coal to the oven through charging opening means in the ovenroof to the full coal conducting capacity of said means while the walls of the oven are hot enough rapidly to evolve gas from the coal and to initiate the coking operation, withdrawing the gas from above the coal in the oven to preventmaterial rise in pressure in the oven, the effectivev coal conducting capacity of said charging opening means being coordinated with the distilling action of the oven on the coal to cause the charge to be distributed by gravity up tofapproximately a uniform heightthroughcut the length of the oven prior tothe coai'becoming sticky due to tar liberation therefrom.

- 5. In a method of operating a horizontally elongated retort coke oven having a substantially single charging opening in the loven roof, that improvement which comprises Vdelivering pulverized coal to said oven atl the top thereof through said opening, and distributing the c oal therein by gravity fromV beneath said opening to adjacent ythe oven roof throughout the length ofthe oven by effecting, by the action of heat on the coal substantially as it enters the oven and by gas withdrawal from the oven during charging, reduction of the angle of repose of the coal to'substantially zero.

6. The method of charging a horizontally elongated fretort coke oven with coal which comprises delivering pulverized coal in a column by gravity to the oven at the top thereof through a substantially single charging opening near theV middle point of the length of the oven While the walls defining the Width ofthe oven are hot, during charging withdrawing gas rapidly from opposite ends of the oven from above the coal, the cross sectional area of said columnland the temperature of said walls and rate of gas withdrawal being such as to cause the coal substantially as it enters the oven to .be distributed by gravity from beneath said Yopening to approximately a uniform height throughout the length ofthe oven.

"57. The method of charginga horizontally elongated, high-chambered, retort coke oven with coal which comprises delivering pulverized coal precipitately by gravity to the oven at the top thereof through asubstantially single charging opening near the middle point of the lengthy ofthe oven to the full coal conducting capacity ofsaid opening while the walls defining the l'width of the oven are hot, during charging withdrawing gas rapidly from yopposite ends of the oven from above the coal, the coal conducting capacity of said opening and the temperature of said walls and rate of gas withdrawal being such as to cause the coal substantiallyas it enters the oven to be distributed'by gravity lfrom beneath said opening to approximately a uniform height throughout the length of the oven.

8, In a method of producing gas and coke from bituminous coal utilizing a horizontally elongated-coke oven the height of which isin the order of a third of its length and the walls of which defining its width are eXteriorly heated, that improvement which comprises charging the oven with pulverized coalby delivering it by gravity to the oven at the top thereof through a substantially single charging opening in the oven roofnear the middle point of its length, said walls; of the oven during charging being hot enough rapidily to evolve gas from the coal, during charging withdrawing the gas from opposite ends of the oven at points above the coal, and allow- `ing the majorportion of thecharge of coal to gravitate into the oven through said opening and substantially as it enters the oven. to i be distributed byV gravity from beneath said opening to approximately a uniform height throughout the length of the oven. Y

A 9. In a method of producing coke and gas from bituminous coal utilizing a horizontal of through said opening to its full coal conducting capacity from a container communicating with said opening while said walls are hot enoughl to cause gas toV be evolved rapidly from the mass of coal when it enters the oven, Vduring charging withdrawing gas through said'oiftakes with sufficient rapidity to prevent material rise in pressure in the oven, and allowing the major portion of the charge to gravitate into the oven and substantially as it enters the oven to bedistributed by gravity from beneath said opening to approximately a uniform heightthroughout the length of the oven.

l0. The method of charging a horizontally elongated, narrow, high-chambered, retort coke oven with coal, which comprises delivering the coal in a pulverized state to the oven at the top thereof through a substantially single charging'opening in the oven roof while the walls of the oven are at a high temperature, said opening being situated between the oven ends, and th-e coal being delivered thereto by gravity, the effective size of said'opening being coordinated. with the relative fluidity of the coal delivered thereto and the fluidity of the coal in the oven during charging to cause the major portion of the charge of coal to flow into the oven and sub- L stantially as it enters the oven to be distributed therein by gravity throughout the length of the oven to approximately a uniform height.

l1. The method of charging a horizontally elongated, high-chambered, retort coke oven having eXteriorly heated Walls, Which comprises delivering pulver-ized coal in a column to the oven at the top thereof through a substantially single charging opening in the oven roof While the Walls of the oven are at a high temperature, such opening being situated between the oven ends and the cross sectional area of said column being such that the coal Will loW into the oven and subf stantially as it enters the oven be distributed therein by gravity to adjacent the oven roof throughout the length of the oven.

12. A method of charging a horizontally elongated retort coke oven Which comprises delivering pulverized coal in a column to the oven at the top thereof through its roof by use of a single charging opening While the oven is hot, the degree of iineness and moisture content of the coal and the temperature of the oven being so coordinated With the height and length of the oven and the cross sectional area of said column that the coal will flow substantially rapidly into the oven and substantially as it enters the oven be distributed therein by gravity to adjacent the oven roof throughout the length of the oven.

In testimony whereof, lf have signed my naine to this specification.

ROBERT M. FOLSOM.

CERTEFICATE OF CRRECTWN.

Patent No. 1,886,948. November s, 1932.

ROBERT M. FLSM.

f. is hreby certified that error appears in the printed specification of the above numbered patent requiring correstion as ows: Page 3,. line 15, for "mrma" read "abnorma"; and that he said Leiters Paent should be read wn this correction therein that the same ay wnfarm t0 the record of the case in the Patent Office.

Signed and sealed this Sd day of January, A. D. 1933.

M.. .L Moore,

Activas; Commissioner of Patents. 

